<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000225604
<NAME> MFS SERIES TRUST III
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<NUMBER> 022
<NAME> MFS MUNICIPAL HIGH INCOME FUND CLASS B
<MULTIPLIER> 1
<S> <C>
<PERIOD-TYPE> 6-MOS
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<NET-CHANGE-IN-ASSETS> (4984104)
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</TABLE>
